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Cam timing goofup?

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Old 01-30-2021, 10:51 PM
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woncom
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Default Cam timing goofup?

First time doing the process on a 01 911 C2.
Setup bank 1, rotated 360 then added cams to bank 2 and buttoned it all up. Rotating the crank, I notice the vario-cam solenoid hopping. Made a video at the link below to show the behavior.


Cam notches still line up after each rotation. The light colored chain links are no longer over the cam sprocket dots however.
Old 01-31-2021, 12:08 PM
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De Jeeper
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How r u holding the cams in place while rotating the motor? I dont think u r suppose to spin it without them. The lifters will cause them to jump around expecially the intake one. There is no way to hold it on the far side. check the dots on the cams. U shulld be able to count 14 links to the next dot. I just did this last night for my variocam pads.
Old 01-31-2021, 02:20 PM
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woncom
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Thanks for chiming in.
Holding with the cam holder tool on the other end of each bank.
14 links? You have 3.4? There are only 7 (maybe 8) links between each colored link.
Old 01-31-2021, 04:11 PM
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3 chain engine vs 5 chain engine? BTW, DeJeeper is referring to links between the dots on the cam gears, whereas the OP is referring to links between the colored links on the cam chains.

Last edited by Weazer; 01-31-2021 at 04:14 PM.
Old 01-31-2021, 07:31 PM
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De Jeeper
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Mine is a 5 chain. I guess i mean 14 hollow areas that the gear tooth would go into. Zoom in u can see the dots on the gears and u can count the links or spaces. My old and new chains did not have the colored links.


Old 01-31-2021, 08:05 PM
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Porschetech3
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Count the Rollers or Pins, like DeJeeper says, 14 is the Magic number. The colored links are only for initial installation, after a revolution they will not line back up except every now and then (mathematical equation).
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Old 01-31-2021, 09:22 PM
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De Jeeper
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Also notice the relief on the intake cam in my pic. When put on the head it will point at the block for 4-6 and cover for 1-3. On the other side of the exhaust cam the slot will be 90* of that relief and should accept the cam locking tool.
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Old 02-01-2021, 10:40 AM
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Imo000
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You've got to support those cams in the middle before you snap them! The spring are putting a huge pressure on the cast iron camshafts and they are not mean to bend. The cam holder at the end is not enough if you are spinning the camshafts around. A small piece of hardwood with some long bolts (2 on each cam) will do the trick.
Old 02-01-2021, 10:55 AM
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Doug996InKC
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Old 02-01-2021, 11:19 AM
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woncom
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Thanks doug996inkc
I have that assembly and will put it on. Was not sure it was safe to rotate with that on as it's not the bearing in contact with the cam.
I can certainly put cam cover back on but want to see that everything is rotating correctly.
Old 02-01-2021, 01:00 PM
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De Jeeper
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Tighten the hold downs fully and then back the bolts of a half turn. This will give enough clearence.

If u need more help with the vairocam pm me and we can talk on the phone. Its real hard to type out the correct way to time it.

Aaron
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Old 02-01-2021, 01:03 PM
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Originally Posted by De Jeeper
Tighten the hold downs fully and then back the bolts of a half turn. This will give enough clearence.

If u need more help with the vairocam pm me and we can talk on the phone. Its real hard to type out the correct way to time it.

Aaron
Shall do Aaron
thanks for the assist offer. Ill follow up soon
Old 02-01-2021, 02:08 PM
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I would use another brace to hold down the middle cylinder cams on both sides.
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